13 results match your criteria: "Guangdong Provincial Engineering Research Center of Crystal and Laser Technology[Affiliation]"

Flat lens-based subwavelength focusing and scanning enabled by Fourier translation.

Nanophotonics

August 2024

College of Physics and Optoelectronic Engineering, Jinan University, Guangzhou 510632, China.

We demonstrate a technique for flexibly controlling subwavelength focusing and scanning, by using the Fourier translation property of a topology-preserved flat lens. The Fourier transform property of the flat lens enables converting an initial phase shift of light into a spatial displacement of its focus. The flat lens used in the technique exhibits a numerical aperture of 0.

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Optical vortex-antivortex crystallization in free space.

Nat Commun

July 2024

Department of Optoelectronic Engineering, Jinan University, Guangzhou, 510632, China.

Stable vortex lattices are basic dynamical patterns which have been demonstrated in physical systems including superconductor physics, Bose-Einstein condensates, hydrodynamics and optics. Vortex-antivortex (VAV) ensembles can be produced, self-organizing into the respective polar lattices. However, these structures are in general highly unstable due to the strong VAV attraction.

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Gram staining can classify bacterial species into two large groups based on cell wall differences. Our study revealed that within the same gram group (gram-positive or gram-negative), subtle cell wall variations can alter staining outcomes, with the peptidoglycan layer and lipid content significantly influencing this effect. Thus, bacteria within the same group can also be differentiated by their spectra.

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Spin-orbit Rabi oscillations in optically synthesized magnetic fields.

Light Sci Appl

August 2023

Department of Optoelectronic Engineering, Jinan University, Guangzhou, 510632, China.

Rabi oscillation has been proven to be one of the cornerstones of quantum mechanics, triggering substantial investigations in different disciplines and various important applications both in the classical and quantum regimes. So far, two independent classes of wave states in the Rabi oscillations have been revealed as spin waves and orbital waves, while a Rabi wave state simultaneously merging the spin and orbital angular momentum has remained elusive. Here we report on the experimental and theoretical observation and control of spin-orbit-coupled Rabi oscillations in the higher-order regime of light.

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Concentration-dependent carbon dot (CD) fluorescence was developed and utilized alongside hyperspectral microscopy as a specific labeling and identification technique for bacteria. Staining revealed that the CD concentration within cells depended on the characteristic intracellular environment of the species. Therefore, based on the concentration dependence of the CD fluorescence, different bacterial species were specifically labeled.

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Identification of DAPI-stained normal, inflammatory, and carcinoma hepatic cells based on hyperspectral microscopy.

Biomed Opt Express

April 2022

Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Guangzhou, 510632, China.

Gross chromatin imbalance and high DNA content are distinct features of various types of cancer cells. However, severe inflammation can also produce similar symptoms in cells. In this study, normal, inflammatory, and carcinoma hepatic cells were stained with 4',6-diamidino-2-phenylindole (DAPI) and investigated by hyperspectral microscopy.

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Higher-order optical rabi oscillations.

Fundam Res

November 2023

Department of Optoelectronic Engineering, Jinan University, Guangzhou 510632, China.

Rabi oscillations express a phenomenon of periodic conversion between two wave states in a coupled system. The finding of Rabi oscillation has led to important applications in many different disciplines. Despite great progress, it is still unknown whether the Rabi oscillating state can be excited in the framework of the higher-order vector vortex regime.

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Gram stain is one of the most common techniques used to visualize bacteria under microscopy and classify bacteria into two large groups (Gram-positive and Gram-negative). However, such an inaccurate classification is unfavorable for bacterial research. For instance, soil-rhizosphere bacteria, () and () have different effects on plants, nonetheless, they are both Gram-positive and difficult to be differentiated.

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In this study, the DAPI staining is firstly reported for use in the identification of hepatic carcinoma cells based on hyperspectral microscopy. Nuclei in cancer cells usually contain more aneuploidies than that in normal cells, leading to the change of DNA content. Here, we stain hepatic carcinoma tissues and normal hepatic tissues with 4',6-diamidino-2-phenylindole (DAPI) which is sensitive to the DNA content as a fluorochrome binds to DNA.

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Super-Necking Crystal Growth and Structural and Magnetic Properties of SrTbO Single Crystals.

ACS Omega

July 2020

Joint Key Laboratory of the Ministry of Education, Institute of Applied Physics and Materials Engineering, University of Macau, Avenida da Universidade, Taipa, Macao SAR 999078, China.

We report on single-crystal growths of the SrTbO compound by a super-necking technique with a laser-floating-zone furnace and study the stoichiometry, growth mode, and structural and magnetic properties by scanning electronic microscopy, neutron Laue, X-ray powder diffraction, and the physical property measurement system. We optimized the growth parameters, mainly the growth speed, atmosphere, and the addition of a TbO raw material. Neutron Laue diffraction displays the characteristic feature of a single crystal.

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Carbon dots (CDs) that exhibit emission over the whole visible spectrum are desired for use in light-emitting diodes (LEDs). Here, CDs displaying tunable fluorescence over the whole visible region are synthesized. Different concentrations of CDs are uniformly dispersed in epoxy resin and coated on 405 nm LED chips to obtain monochrome blue, cyan, green, yellow, red, and deep red LEDs that yield a color gamut covering 99.

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For practical applications of carbon dots (CDs), a major challenge is to prevent the notorious aggregation-caused quenching (ACQ) effect. Herein, a new type of CDs (CD1) has been developed that can transform from ACQ to an enhancement of fluorescence by aggregation-induced emission (AIE). The blue fluorescence of the CDs is suppressed by ACQ.

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Dual-type hyperspectral microscopic imaging for the identification and analysis of intestinal fungi.

Biomed Opt Express

September 2018

Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Guangzhou 510632, China.

A method based on a dual-type (transmission and fluorescence) hyperspectral microscopic image system was developed to identify species of intestinal fungi. Living fungi are difficult to identify via transmission spectra or fluorescence spectra alone. We propose an identification method based on both fluorescence and transmission spectra that employs a series of image processing methods.

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